If I have a smartphone line on my account that is eligible to upgrade, can I just purchase the xoom for the 199, activate it on that line temporarily. Then just reactivate my smartphone on that line and use the xoom as WiFi only? I cannot find the answer to this anywhere. Reason I'm wondering is I would like to get this as a gift and have a couple of upgrades to spare. I obviously don't want to pay someone else's data plan per month lol